(a) Field of the Invention
The present invention relates to an improved structure for a connector of a cigarette lighting device of cars, more particularly directed to improving load bearing stability of external connections of the connector of the cigarette lighting device of cars and to obviating poor electrical contact. A lateral end of an electrically conductive elastic plate projecting slightly from an outer peripheral side of a jack is provided with a vertically depressed slide groove, which is provided with a recessed or bulging oblique face in a suitable position. A rear end of a housing of the jack is provided with annular threads. The slide groove is insertably provided with a push block that matches a bottom side of a groove hole of the slide groove and that is capable of filling a depression of the slide groove. The push block has a flange or recessed groove at a rear end. The threads at the rear end of the housing of the jack threadedly engage a turning nut. The turning nut has a front end provided with a recessed groove or a flange for inter-engagement with the flange or recessed groove of the push block. The housing of the jack is inserted into an insert hole of the cigarette lighting device of a car. By rotating the turning nut, the push block is brought to displace forwardly and rearwardly, with the oblique face guiding the push block to project upwardly to abut against the inner wall of the insert hole to thereby secure the jack and to enhance the load bearing ability and stability of external connections of the connector of the cigarette lighting device. Besides, slippage, improper electrical contact or difficult insertion may be prevented.
(b) Description of the Prior Art
For connection of electrical circuits, cars are equipped with cigarette lighting devices having circular sockets. For business, travel and information transmission, mobile phones, satellite communication devices, liquid crystal display devices, etc. are very popular. These devices are also turned on when in cars. And cars also provide a source for charging these devices. Besides, most countries have prohibited use of hand-held communication equipment when driving. Therefore, hand-free devices becomes necessary, and cigarette lighting device sockets do not merely permit electrical connection and extend to include article support seats, hand-free charging seats, extension seats, etc. Load bearing has therefore become a function of cigarette lighting device sockets. However, conventional cigarette lighting device sockets are formed by bending metallic electrically conductive electrodes into a suitable shape to be clamped in the socket housing, with the outer edges projecting from the outer end face of the socket housing. Therefore, it is inserted into a circular insert hole of the cigarette lighting device, the internal diameter of the circular insert hole can clamp the metal electrically conductive electrode to cause it to bend down inwardly to achieve a stretching supporting force and to connect to the electrically conductive plate on the hole side to achieve electrical connection. However, since the metallic electrically conductive plate achieves pressing and stretching by virtue of the elasticity and bending ability of the material of the electrode, it is not easy for the conductive plate to provide a pressing force and a strong stretching elastic force at the same time. Besides, due to differences in the bent shape and size as well as the selection of metallic material, oftentimes there is excessive resistance, which prevents easy insertion and removal. Sometimes, breakage even occurs. If the gap between the socket and the insert hole are increased, the connection may easily become loosened when driving on rugged surfaces or at a high speed. There may be unstable signal reception, interrupted signal reception or even damage due to falling of the electrode.